This paper determines the interactive effects of information technologies(IT) on corporate performances. IT was measured inclusively in terms of technology level, information level, functional level, and management level. Corporate performances were composed of the effectiveness of IT and the financial performance of a corporation. The effectiveness of IT was measured in terms of satisfaction with the support of IT department and with output information, whereas financial performance of corporation was measured in terms of market growth and profitability. Theoretical and empirical analyses lead to the followings. In the theoretical aspect, IT in a corporation needs to be measured broadly. And a study of IT related to corporate performance needs to use either a conversion effectiveness model or an intermediate effect model rather than a direct effect model. In the empirical aspect, the effectiveness of IT within an organization improves with some of the interactive effect of ITs including technology level, information level, functional level, and management level. So do some of the financial performances of a corporation.